The power supply is a very important appliance in college, vocation school, high school, acadamic institution, and test lab. As the power supply manufacturer we have various types of power supply in our products, DC power supply, AC power supply, AC and DC power supply. In DC power supply, there is a linear DC power supply and switching DC power supply with different working principles, and there are programmable DC power supply and normal DC power supply with the different using methods. Insulated transformer makes the AC power supply more safety and the innovational technology makes the voltage and current adjustable for the AC power supply. There is also some special power supply for physical, engineering, mechanical, and chemical experiments. The single-phase and three-phase varic is an ideal adjustable transformer for the industry.